Steps to reproduce

• Open a Wikidata item with a JavaScript enabled browser.
• Enter a new label and click on save.

-> The new label is shown in the page and in the HTML title.
-> The page has exactly the same content as if you would reload the page.
-> The page is not reloaded because the change is saved by AJAX.

• Click on a random link.

-> A new page is loaded.

• Click on the back button of the browser.

-> The previous page is shown.
-> But it contains the old label in the page and in the HTML title.

Expected result:
-> The page should contain the same content as if you would reload the page.

To implement this the JavaScript must remember the saved changes and replay them on reopening the page by back button.

Version: master
Severity: minor